Water Purifier Buying Guide
Water purifier is necessary nowadays especially if you use underground water for drinking as these can contaminants. Water filters are the more permanent solution. Many types of water filters are made, and they range widely in sophistication and price. They may use reverse-osmosis, activated carbon, or ultra-violet rays to clean or purify water. Before you start looking for a water purifier you should also keep some points about water in mind:
- Water should deliver essential nutrients and minerals like calcium,magnesium, potassium and trace elements needed to live.
- Water helps in balancing out the acidic state of the body by being alkaline. Acidic condition can cause chronic diseases such as cancer, arthritis, diabetes and osteoporosis.
- Water should have antioxidant properties. Oxidization makes cell breakdown faster, water with no impurities can prevent it.
- There can be as high as 2000 contaminants in water, you should strive to remove these from your drinking water.
Water Purification Methods
Different water purifiers use different methods of purification. They might have different purification stages. A higher number of purification levels ensure cleaner drinking water. However it can eliminate essential chemicals also from water. Hence you should know the types of purification and what is appropriate for the water tht you have.
Pre filter purification
Pre-filters are designed to remove silt, dust and dirt particles from the water before it enters the main filtration process. Candle-filter or sediment-filter are few pre-filter purification methods.
Candle-filter purification
There is a special multi layer micro porous candle filter to remove impurities like carbon, charcoal, oil, vegetable oil and other suspended materials.
Sediment Filters
Sediment Cartridges trap particulate matter such as silt, sand or carbon fines. These are useful when water is from wells, old municipal water systems, old house water. Sediment cartridges are commonly used as pre-filters to RO (reverse osmosis) systems.
Health and taste cartridge
Taste and odor filter cartridges most commonly contain activated carbon. Activated carbon removes chlorine and organic matter making the water less distasteful to consumers. In process applications such as reverse osmosis (RO) these cartridges are pre-filters that protect the RO TFM membranes from chlorine damage.
Reverse osmosis (RO)
Reverse osmosis is used to remove dissolved impurities from water through the use of a semi-permeable membrane. It comprises of activated carbons that pre-filters the water making it safe for drinking.
This should be used when water is from bore well or water tanker. Otherwise high TDS levels in the water should also use RO systems for water purification.
For places where the water is hard, RO water purifier is essential.
The problem with reverse osmosis however is that all the minerals are removed from the water. These include the healthy ones.
RO systems can be slow and contaminants with molecules that are the same size or smaller than water like chlorine can pass through. Chlorine can also damage the permeable film which will cause impurities mixing with the clean water.
Ultra-violet(UV) filtration
Ultrafiltration removes dissolved solids of and above the size 0.005-0.1 microns. It is capable of removing solids, bacteria and viruses.
NON-ELECTRIC WATER PURIFIER
These are of two types:
- Online: Fixed to the mouth of taps, these purifiers are portable and need no electricity.Made of plastic, the filter candle usually has a resin filter that needs to be changed every month.
- Offline or Storage Type: These are also known popularly as water filters. These don’t need electricity or plumbing. These purifiers have a combination of sediment filters and activated carbon filters.
These storage type water purifiers gcan generally ore 18-26l of water. This type of storage is very helpful in places facing water shortage.
Body Type
Steel
Steel ensures total safety, hygiene and durability, for complete peace of mind.
Aluminium
It reacts with salts and minerals in the water to produce aluminium oxides which are toxic and implicated in brain disease.
ELECTRIC WATER PURIFIER
Connected to pipelines, they have a combination of sediment filters and activated carbon. They employ the UV purification system or the Reverse Osmosis(RO) system. These are of two types:
UV System
Look out for the one with voltage stabilizer and LCD screen. Available in counter top and kitchen wall-mounted models, the UV rays are well contained and safe.
Kent UV Water Purifier
RO System
These systems get rid of disease bearing bacteria and viruses, and pollutants such as insecticides and cancerous dyes. They make hard water drinkable and are best for those living in coastal areas.
Kent Mineral RO Water Purifier
Mounting
Wall Mounted
Principles of Various Water Purifying System:
| Equipment | Whats’s Eliminated? | How does it work? |
| Sediment filters/cartridges | Suspended Matter | Cartridges are made of fibre (usually made of polypropylene).They hold back particles to pass through. |
| Activated carbon filter | Dissolved chemicals | Impurities stick to carbon layer, ridding tap water of odour, colour and bad taste. |
| Reverse Osmosis(RO) | Bacteria, Viruses, Salts, Proteins,Dyes and Other Constituents | Has a semi-permeable membrane. Water is pumped through the membrane. (As the pure water concentration increases, greater pressure is required; hence, RO systems need electricity.) RO is needed where there is hard water. |
| UV Purification | Disease-Bearing or other harmful micro-organisms | The first is a filter that removes impurities, then uses high-energy UV rays from a UV lamp fitted inside the purifier to eliminate micro-organisms. Water is exposed to these rays at a particular intensity for an optimum period of time. |
FEATURES OF WATER PURIFIER
Flow rate
Beyond a prticular flow rate of water, bacteria can pass thorugh the system. On the other hand it should not be slow as you will need to wait longer times. Typical purifiers have a flow rate 1-2 litres per minute.
Weight
The weight of your water filter is important as it should be mountable on wall else it will occupy some space in the kitchen.
Body
The water purifier body should be durable, rust proof and attractive to go with the kitchen decor. There are different materials used like Aluminium and ABS. Points to keep in mind when buying a water purifier:
- Quality of water: The salt content – high or low – should determine your choice.
- Convenience: Depending on where you would be collecting the water, select an online,offline or inline systems.
- Budget:Most purifiers are pocket friendly. Also, electricity consumed in most inline purifiers are not more than 25W.
Global Certification
Check for global certifications like WQA (USA) Gold Seal mark for RO or UV systems as many local assemblers import components from local or non-reputed Chinese suppliers assembles units in India.